Poa pratensis L. named &#39;NE-KYB-05-001&#39;

ABSTRACT

A new and distinct variety of Kentucky Bluegrass named ‘NE-KYB-05-001’ (trade name Bella), is characterized by its vegetative only propagation, improved shade and drought tolerance, dwarf-like and dense growth habit, dark green foliage and shorter leaves compared to other Kentucky bluegrass varieties.

LATIN NAME OF THE GENUS AND SPECIES

The Latin name of the genus and species of the novel variety disclosedherein is Poa pratensis L.

VARIETY DENOMINATION

The inventive variety of Poa pratensis L. disclosed herein has beengiven the variety denomination ‘NE-KYB-05-001’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct perennial variety ofPoa pratensis L.

‘NE-KYB-05-001’ is a result from the breeding program at the Universityof Nebraska, Lincoln. The parent grasses are unknown at the currenttime. ‘NE-KYB-05-001’ has been vegetatively propagated since it is apoor seed producer, which makes it unique and different than any otherPoa pratensis L. It is anticipated that the plant of this invention willbe marketed under the synonym Bella as a trade name. ‘NE-KYB-05-001’ isso identified in pictures and morphological and agronomic charts of thisdisclosure.

SUMMARY OF THE INVENTION

‘NE-KYB-05-001’ is a distinctive variety of Poa pratensis L. being adark green, extremely low-growing Kentucky bluegrass cultivar, havingsuperior high temperature adaptation and drought resistance.‘NE-KYB-05-001’ is a very poor seed producer, making it suitable forvegetative reproduction only, such as sprigs, rhizomes, plantlets, orsod. ‘NE-KYB-05-001’ is adapted for use in the cool-humid, cool-aridareas in the US and Canada, zones 2 to 7 of the Plant Heat Zone Map, andtransition zone 8 (FIG. 1).

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1: ‘NE-KYB-05-001’ in a shade study at UN; Mead, Nebr.

FIG. 2: ‘NE-KYB-05-001’ field at Newton, Ga. (transition zone 8).

FIG. 3: ‘NE-KYB-05-001’ test plots at MSU, Miss. ‘NE-KYB-05-001’ isfirst on the left at lower corner, in the center of the plots and atright upper corner.

FIG. 4: ‘NE-KYB-05-001’ test plots at UN, Nebr. ‘NE-KYB-05-001’ is on1st row second to left, 2nd row 3rd from left and 3rd row 1st from left.

FIG. 5: ‘NE-KYB-05-001’ close up.

FIG. 6: ‘NE-KYB-05-001’ plug.

FIG. 7: Plant height comparison: ‘NE-KYB-05-001’ top; Midnight bottom.

DESCRIPTION OF THE NEW VARIETY

The following is a detailed description of the new grass variety, basedupon observations of the plant grown in field plots at the University ofNebraska, John Seaton Anderson Turfgrass Research Facility located nearMead, Nebr. ‘NE-KYB-05-001’ is an outstanding Kentucky bluegrasscultivar that is drought resistant and tolerant of high temperatures.Its drought resistance characteristics make it suited for use wherewater conservation is an issue. Its heat tolerance makes it suitable foruse in the transition zone. ‘NE-KYB-05-001’ is low-growing and requiresinfrequent mowing, making it an excellent choice for lawns which canbenefit from reduced mowing schedule and for sites that are difficult tomow, such as slopes and banks. ‘NE-KYB-05-001’ requires low fertilizerinput and grows well on soils ranging from sand to heavy clay.‘NE-KYB-005-001’ can only be established vegetatively by sprigs,rhizomes, plugs or sod. ‘NE-KYB-05-001’ has also an excellent shadetolerance compared to other bluegrasses. Its dark green color and lowgrowth habit give it a highly appealing turfgrass quality andappearance.

Growth Habit and Dimensions

‘NE-KYB-05-001’ was compared to 19 other cultivars of Kentucky bluegrassat the University of Nebraska John Seaton Anderson Turfgrass ResearchFacility located near Mead, Nebr. starting in September 2005. Treatmentsfor all cultivars were the same.

The Analysis of Variance (ANOVA) indicated that cultivars differedsignificantly for most variables measured (Table 1). Cultivars werequite similar in days to flowering, but ‘NE-KYB-05-001’ flowered laterthan Blue Moon, Absolute, and Kenblue (Table 2). ‘NE-KYB-05-001’ is alow growing cultivar. It had the lowest foliage height of any of thecultivars studied (Table 2). ‘NE-KYB-05-001’ had nearly half the plantfoliage height of the nearest low growing cultivar. In addition to thelow foliage height, ‘NE-KYB-05-001’ had the shortest leaf length of anyof the cultivars (Table 2).

‘NE-KYB-05-001’ has a dwarf-like growth habit, which would require lessfrequent mowing. ‘NE-KYB-05-001’ ranked intermediate in leaf width withPrinceton 105 having greater leaf width and Park having finer leafwidth. Even though ‘NE-KYB-05-001’ has a dwarf-like growth habit, itstill ranked among the cultivars with the greatest amount of plantspread (Table 2). ‘NE-KYB-05-001’, Absolute, and NuDensity had thelowest incidence of stem rust [Puccinia graminis f.sp. poae (Pers.)],which was the only disease that occurred during this study.

‘NE-KYB-05-001’ had the lowest seed yield (110 lbs acre⁻¹) of thecultivars studied, and it had the poorest seed germination (12%) (Table3). Both of these characteristics make it impractical to produce‘NE-KYB-05-001’ as a seeded cultivar; therefore ‘NE-KYB-05-001’ has tobe reproduced vegetatively. ‘NE-KYB-05-001’ and Absolute had theshortest panicle length, and ‘NE-KYB-05-001’ had the lowest flag leafheight, and shortest flag leaf length of the cultivars studied (Table3).

TABLE 1 Analysis of Variance for Kentucky bluegrass cultivar comparisonswith ‘NE-KYB-05-001’ conducted during the 2005 to 2007 growing seasons.Mean Squares of the traits Source df HD^(†) FD FH LL LW PL PS FLH FLLFLW SR Rep 2 6.07 45.2 55.6 12.1 0.0006 4.48 20.42 3.88 15.93 0.013 3.03Variety 19 90.5 24.7 141.2^(**) 34.9^(**) 0.002^(**) 6.79^(**) 6.28^(**)48.71^(**) 8.65^(**) 0.007^(*) 1.44^(**) Error 38 17.9 7.3 15.1 2.60.0003 0.9 2.8 7.5 3.0 0.003 0.3 CV 4.1 2.4 12.4 9.1 3.9 9.9 11.4 17.725.2 9.7 18.2 ^(†)HD—Heading Date FD—Flowering Date FH—Foliage HeightLL—Leaf Length LW—Leaf Width PL—Panicle Length PS—Plant Spread FLH—FlagLeaf Height FLL—Flag Leaf Length FLW—Flag Leaf Width SR—Stem Rust^(*)Significant at 5% level ^(**)Significant at 1% level

TABLE 2 Kentucky bluegrass cultivar comparisons with ‘NE-KYB-05-001’conducted during the 2005 to 2007 growing season. Stem HD FD FH LL LW PSRust No Variety (days) (days) (cm) (cm) (cm) (cm) (1-9) 1 Absolute 99108 30.3 16.80 0.47 14.8 1.9 2 ‘NE-KYB- 108 115 13.3 9.20 0.47 15.4 1.905-001’ 3 Blue Moon 98 109 31.7 17.20 0.45 14.9 3.9 4 Caliber 97 11548.9 25.80 0.48 16.9 3.0 5 Common 98 114 37.3 19.60 0.45 15.1 3.6 98/806 Everest 109 116 25.1 14.10 0.45 13.2 4.3 7 Everglade 111 116 29.516.50 0.44 13.6 2.6 8 Impact 106 113 28.7 16.30 0.44 11.8 2.5 9 Kenblue92 106 39.3 22.40 0.44 17.1 3.6 10 Liberator 105 112 26.5 15.50 0.45 143.3 11 Midnight 93 113 31.8 20.80 0.43 17.1 3.0 12 NuBlue 102 116 35.420.10 0.44 15.4 3.9 13 NuDensity 104 113 30.8 16.00 0.43 13.7 1.9 14NuGlade 107 115 27.6 16.30 0.45 12.4 3.3 15 Park 97 113 36.4 19.80 0.4215.1 3.2 16 Perfection 111 119 29.8 16.90 0.44 15.4 2.5 17 Princeton 103113 34.2 20.30 0.52 14.6 2.4 P-105 18 Rugby II 100 112 34.9 17.00 0.4514.6 3.4 19 Total Eclipse 105 112 27.9 15.90 0.43 13.4 3.3 20 Tsunami104 113 30.8 16.90 0.43 13.6 3.3 LSD (5%) 6.9 4.5 6.4 2.7 0.03 2.8 0.9^(†)HD—Heading Date (days to heading), FD—Flowering Date (days toflowering), FH—Foliage Height (cm), LL—Leaf Length (cm), LW—Leaf Width(cm), PS—Plant Spread (cm), and SR—Stem Rust (1-9 visual rating with 1 =0-10% and 9 = 90-100% disease incidence)

TABLE 3 Kentucky bluegrass cultivar comparisons with ‘NE-KYB-05-001’conducted during the 2005 to 2007 growing seasons. SY PL FLH FLL FLW(lbs PB No Variety (cm) (cm) (cm) (cm) acre⁻¹) (%) 1 Absolute 7.6 14.05.1 0.59 650 92 2 ‘NE-KYB-05-001’ 7.6 10.2 3.5 0.59 110 12 3 BlueMoon9.7 12.6 6.2 0.53 810 92 4 Caliber 14.9 24.7 9.3 0.54 711 92 5Common98/80 9.9 20.7 8.0 0.49 749 85 6 Everest 8.4 11.2 5.7 0.59 668 927 Everglade 8.7 11.8 6.8 0.59 679 88 8 Impact 9.2 19.2 8.1 0.55 839 80 9Kenblue 9.9 21.7 7.3 0.45 767 85 10 Liberator 8.6 13.0 6.0 0.53 709 9011 Midnight 9.9 16.9 7.0 0.47 279 90 12 MN Park 9.6 19.3 7.6 0.49 630 8813 NuBlue 9.0 15.5 5.3 0.49 813 90 14 NuDensity 8.6 12.2 7.2 0.58 875 8815 NuGlade 9.2 13.6 6.4 0.61 788 85 16 Perfection 9.0 13.4 7.0 0.57 85085 17 Princeton P-105 10.5 12.2 11.9 0.59 360 92 18 Rugby II 9.5 16.57.3 0.59 868 78 19 Total Eclipse 9.9 14.3 6.5 0.53 790 75 20 Tsunami 8.614.3 6.2 0.54 573 92 LSD (5%) 1.5 4.5 2.9 0.09 151 14 ^(†)PL—PanicleLength (cm), FLH—Flag Leaf Height (cm), FLL—Flag Leaf Length (cm),FLW—Flag Leaf Width (cm), SY—Seed Yield (lbs acre⁻¹) and PG—PercentGermination (%)

Drought Tolerance

‘NE-KYB-05-001’ was tested and compared with 22 other Kentucky bluegrasscultivars in a turfgrass evaluation experiment initiated on September 05at University of Nebraska John Seaton Anderson Turfgrass ResearchFacility. Irrigation was performed at a 60% ET deficit level to evaluatecultivar performance under drought stress conditions. Normal irrigationfor Kentucky bluegrasses in this region is generally conducted at ETparound 80-90%.

The 2006 growing season was the establishment year for this study.‘NE-KYB-05-001’ had the second lowest density rating during theestablishment year (Table 4). This was a result of the other cultivarsbeing seeded and ‘NE-KYB-05-001’ being established from vegetativesprigs. Seeding gave the other cultivars an advantage during theestablishment year. Despite low density ratings during establishmentyear, ‘NE-KYB-05-001’ had the highest quality ratings in September andNovember, and the second highest quality rating scores in July andAugust. In addition to that, ‘NE-KYB-05-001’ had the darkest greengenetic color rating for all of the cultivars evaluated (Table 4). Withits natural and unique dark green color ‘NE-KYB-05-001’ will requireless Nitrogen to maintain the same level of green color compared toother bluegrasses.

In 2007, ‘NE-KYB-05-001’ had spring density ratings that exceeded manyvarieties (Table 5). Its summer density ratings were ranked third alongwith Perfection and Caliber. These results support ‘NE-KYB-05-001’ as acultivar that is capable of producing a dense high quality turf.‘NE-KYB-05-001’ consistently ranked among the highest in turfgrassquality ratings during the 2007 growing season (Table 5). This trendcontinued in the 2008 growing season where ‘NE-KYB-05-001’ had thehighest ratings for spring green up, for spring and summer density; andfor quality for May and June (Table 6). ‘NE-KYB-05-001’ forms a highquality, dense, dark green turf even under deficit irrigation conditions(60% ET), demonstrating to have a high level of drought tolerance.

TABLE 4 Mean turfgrass color, density, and quality ratings for Kentuckybluegrass cultivar evaluation study. Data are from 2006. Color QualityCultivars August Density August July August September November Absolute6.7 9.0 6.7 5.7 6.3 5.0 ‘NE-KYB-05-001’ 9.0 7.3 8.3 7.7 8.3 7.0 BlueChip 7.0 8.7 6.7 6.0 5.0 4.3 Blue Moon 7.3 9.0 7.3 6.7 6.7 5.3 Caliber5.7 9.0 5.0 4.7 5.3 4.0 Common 6.0 8.7 5.7 5.3 6.0 4.7 Everest 9.0 8.78.3 8.0 8.0 6.7 Everglade 8.3 9.0 8.0 7.0 6.0 6.0 Impact 8.7 9.0 8.0 7.78.0 5.3 Kenblue 5.3 6.0 4.3 6.7 3.7 4.3 Liberator 8.7 8.0 8.3 8.0 8.06.3 Limousine 6.7 9.0 6.0 5.0 4.7 3.0 Midnight 4.0 9.0 4.3 3.7 3.7 4.3NuBlue 6.7 9.0 6.7 5.3 6.0 5.7 NuDensity 8.7 9.0 8.7 7.7 8.3 6.7 NuGlade8.3 9.0 7.7 6.7 7.7 6.3 Park 5.3 9.0 5.0 4.7 4.7 4.0 Perfection 8.3 9.08.0 7.0 7.7 6.3 Princeton P-105 8.0 9.0 7.7 7.3 6.7 6.3 Rambo 8.7 9.08.0 7.7 6.7 6.0 Rugby II 7.3 9.0 6.7 5.3 6.0 5.0 Total Eclipse 7.3 9.07.3 6.3 7.3 5.7 Tsunami 7.7 9.0 8.0 8.0 7.3 6.7 LSD (5%) 0.6 0.5 0.7 0.60.8 0.5

TABLE 5 Mean turfgrass density, and quality ratings for Kentuckybluegrass cultivar evaluation. Data are from 2007. Density QualityCultivar Spring Summer Fall April May July Aug Sept Oct Absolute 8.0 8.39.0 3.0 5.7 5.7 6.7 5.7 6.7 ‘NE-KYB-05-001’ 7.7 8.0 9.0 4.0 7.7 7.3 7.37.7 7.0 BlueChip 8.0 6.0 9.0 2.7 6.3 5.7 5.7 5.7 6.7 BlueMoon 7.0 6.39.0 2.3 5.7 6.3 6.3 5.0 7.3 Caliber 7.3 8.0 8.7 2.7 5.7 6.0 6.0 5.7 7.0Common 6.7 6.7 8.7 2.0 4.0 5.0 5.0 6.0 5.3 Everest 7.3 6.7 8.7 2.7 6.76.7 7.3 7.0 7.0 Everglade 7.0 7.7 9.0 2.3 6.3 7.0 7.3 7.3 6.7 Impact 7.77.3 9.0 2.7 6.0 7.0 6.7 6.3 7.0 Kenblue 6.3 5.0 8.7 2.0 4.0 4.7 4.3 4.35.0 Liberator 8.0 8.7 9.0 4.3 7.0 7.7 7.7 6.7 7.3 Limousine 8.7 6.7 8.74.0 6.3 6.3 6.7 6.7 7.3 Midnight 6.0 5.3 9.0 2.0 3.7 4.3 4.0 4.0 4.7NuBlue 8.0 7.7 8.7 4.3 6.0 6.0 6.0 6.0 7.3 NuDensity 7.3 7.3 8.7 4.0 6.06.7 7.0 7.0 6.3 NuGlade 7.0 8.3 9.0 2.7 6.0 6.7 7.3 6.7 7.7 Park 6.3 6.39.0 1.0 3.7 4.7 4.3 4.7 5.3 Perfection 8.0 8.0 8.7 2.7 7.0 7.3 7.7 6.77.3 Princeton P-105 7.3 6.3 8.7 2.7 5.0 5.3 4.7 5.0 6.7 Rambo 7.3 7.08.7 3.0 6.3 7.3 7.3 6.0 7.0 Rugby II 7.7 7.7 9.0 2.3 5.7 5.7 5.7 5.7 6.0Total Eclipse 7.3 6.7 9.0 3.3 6.7 7.0 6.7 6.3 7.3 Tsunami 7.0 8.7 9.03.0 6.3 7.3 8.0 7.0 7.7 LSD (5%) 0.9 0.5 ns 0.6 0.6 0.6 0.7 0.9 0.6

TABLE 6 Mean turfgrass spring green-up, density, and quality ratings forKentucky bluegrass cultivar evaluation. Data are from 2008. SpringDensity Quality Cultivar Green-up Spring Summer May June July Absolute7.0 8.0 7.0 6.3 6.7 6.3 ‘NE-KYB-05-001’ 8.3 8.7 8.3 7.7 7.3 6.0 BlueChip 7.0 8.0 7.0 5.7 4.7 5.3 Blue Moon 6.3 8.0 6.3 6.7 6.7 6.7 Caliber7.3 7.3 7.3 4.7 3.0 5.0 Common 6.3 7.7 6.3 4.3 2 7 4.0 Everest 6.7 8.36.7 6.7 7.0 6.7 Everglade 6.7 8.0 6.7 7.0 5.7 6.0 Impact 7.0 8.3 7.0 6.77.0 6.7 Kenblue 5.0 6.0 5.0 4.0 2.7 4.0 Liberator 7.7 8.3 7.7 6.7 6.37.0 Limousine 7.7 8.7 7.7 5.7 5.3 4.3 Midnight 5.7 6.0 5.7 3.7 2.3 4.0NuBlue 7.3 7.7 7.3 5.3 3.7 5.3 Nuoensity 7.3 8.7 7.3 7.0 7.0 7.3 NuGlade6.3 8.0 6.3 6.7 6.0 5.7 Park 7.3 7.7 7.3 4.0 2.0 4.0 Perfection 6.3 8.36.3 7.0 6.7 6.7 Princeton P-105 7.0 8.0 7.0 6.7 6.0 5.7 Rambo 7.0 8.37.0 7.3 7.7 7.0 Rugby II 6.7 7.7 6.7 6.7 6.0 5.7 Total Eclipse 7.0 7.77.0 6.3 6.0 6.0 Tsunami 6.7 8.0 6.7 6.7 6.7 7.0 LSD 5% 0.8 0.5 0.7 0.60.5 0.6

Shade Tolerance

An experiment was initiated in 2006 at the University of Nebraska JohnSeaton Anderson Turfgrass Research Facility located near Mead, Nebr.with ‘NE-KYB-05-001’, Thermal Blue, and Midnight to compare shadetolerance among these three bluegrasses. Plots were mowed weekly at 2.5inches and clippings were removed. Plots received 3.0 lbs N per 1000 ft²per growing season with applications made at 1.0 lbs per 1000 ft² inMay, September, and October. No fungicides or insecticides were appliedto the plots. Post emergence herbicides were applied as needed toprevent weed encroachment problems. All 3 varieties were maintained at60% shade conditions, during the entire experiment. Shade conditionswere achieved by using a special shade cloth which provided 60%reduction of incident sunlight.

The Analysis of Variance (ANOVA) showed grasses differed significantlyat 1% level in spring green-up, color, density and quality when exposedto shade conditions (Table 7). ‘NE-KYB-05-001’ maintained a darker greencolor and greened up earlier than Thermal Blue or Midnight (Table 8).‘NE-KYB-05-001’ had superior turfgrass quality and density under theshaded conditions of this study. The higher turfgrass quality wasprimarily a result of ‘NE-KYB-05-001’ maintaining darker green color,better density and lower heights than Thermal Blue or Midnight (FIG. 2).Reduced green color and etiolated growth are common responses of plantslacking tolerance to reduced light intensity associated with shadedgrowing conditions. ‘NE-KYB-05-001’ demonstrated plant growth responsesassociated with superior shade tolerance.

TABLE 7 Analysis of variance for three Kentucky bluegrass cultivarsgrown at 60% shade at University of Nebraska Research Facility nearMead, NE. Data are from 2008. Mean Squares Spring Green-up Color DensityQuality Source df March June Spring Summer May June July Rep 2 2.33 0.780.11 0.11 0.11 0.33 0.44 Genotypes 2 4.3** 23.11** 5.44** 9.78** 11.44**17.33** 14.78** Error 4 0.17 0.11 0.11 0.11 0.11 0.17 0.28 CV (%) 5.68.7 4.6 5.2 5.8 7.7 10.1 ^(**)Significant at the 0.01 level

TABLE 8 Mean turfgrass spring green-up, color, density and qualityratings for three Kentucky bluegrass cultivars grown in a shadeevaluation study located at the University of Nebraska John SeatonAnderson Turfgrass Research Facility near Mead, NE. Plots weremaintained under a shade environment of 60% reduction of incidentsunlight. Data are from 2008. Mean Spring Green-up Color Density QualityGenotypes March June Spring Summer May June July “NE-KYB-05-001” 8.7 8.78.7 8.3 8.0 8.0 7.7 Midnight 6.3 3.3 6.0 5.0 4.3 3.3 3.3 Thermal Blue7.0 4.7 7.0 6.0 5.0 4.7 4.7

1. ‘NE-KYB-05-001’, is a new and distinct variety of Kentucky bluegrass,substantially as herein illustrated and described, characterized by itsdistinctive and unique combination of several characteristics such as:exclusively vegetative propagation, dark green foliage, shorter leaflength, improved shade and drought tolerance and slow vertical growthhabit.